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This playground shows you a few different ways to get device info via IOKit.
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| // This playground shows you a few different ways to get device info via IOKit. | |
| // If you want to explore IOKit and look for interesting data I would download | |
| // the Additional Developer Tools from Apple and use the IORegistryExplorer app. | |
| // It makes it super easy to poke around in the IOKit planes. | |
| import IOKit | |
| import Foundation | |
| // For convient access we can make a computed getter for the PlatformExpert. | |
| // Traditionally this has been where you go to find all sorts of data about the | |
| // Mac. With Apple Silicon though there seems to be a shift to store product | |
| // data over in a new service. | |
| // | |
| // The class inheritance of this object is: IOPlatformExpertDevice : IOService : IORegistryEntry : OSObject | |
| // | |
| // We will cover that below as well. | |
| private var platformExpert: io_service_t { | |
| IOServiceGetMatchingService(kIOMainPortDefault, IOServiceMatching("IOPlatformExpertDevice")) | |
| } | |
| // This domain is just to show you how to find a different one. In this case it's the power management | |
| // domain where you can find things like Clamshell State. | |
| private var pmRootDomain : io_service_t { | |
| IOServiceGetMatchingService(kIOMainPortDefault, IOServiceMatching("IOPMrootDomain")) | |
| } | |
| // This method will take a IOKit key as a String and then return a string if it finds a value | |
| // in the sepcified IOKit domain. | |
| // The types in these examples are just CFBoolean, CFString or CFData on my Mac, so that's all I handle | |
| // in this example. | |
| // | |
| // If you are new to working with CFTypes they aren't that scary. A lot of methods | |
| // will return a clear type like CFString or CFData and you can just cast those in | |
| // most cases. Some methods, like the one we are using here, return an opaque CFRef. | |
| // The simplest way to convert them cleanly to Swift is to check and see what the type | |
| // of data held in the CFRef is with CFGetTypeID() and then compare that to known | |
| // CFTypes. | |
| // | |
| // For debugging you can just dump a CFRef to the console with CFShow(). | |
| // | |
| // Make sure you take the retained value of the IOKit container. That way ARC knows to release it. | |
| func getIOPlatformString(_ key: String, domain: io_service_t) -> String? { | |
| let iokValue = IORegistryEntryCreateCFProperty(domain, | |
| (key as CFString), | |
| kCFAllocatorDefault, | |
| 0).takeRetainedValue() | |
| let typeID = CFGetTypeID(iokValue) | |
| if typeID == CFStringGetTypeID(), | |
| let iokString = iokValue as? String { | |
| return iokString | |
| } | |
| if typeID == CFBooleanGetTypeID(), | |
| let iokBool = iokValue as? Bool { | |
| return String(iokBool) | |
| } | |
| if typeID == CFDataGetTypeID(), | |
| let data = iokValue as? Data, | |
| let iokString = String(data: data, encoding: .utf8)?.trimmingCharacters(in: .newlines) { | |
| return iokString | |
| } | |
| return nil | |
| } | |
| // On Apple Silicon there seems to be a move to use another area of the IOService plane, AppleARMPE. | |
| // Inside there is a "product" class that contains the same basic info as the PLatformExpert | |
| // but it also has more info as well. Notice that I can also create and release the IOKit Object | |
| // right after using it in my method as well. | |
| // | |
| // The class inheritance of this object is: IOPlatformDevice : IOService : IORegistryEntry : OSObject | |
| // | |
| // Just to show something different we get our registry entry here in a different way. | |
| // If we use a mach_port to search from then we can just sepcify the path to the entry that | |
| // we want a snapshot of. After that we can convert the CFType to a String and print it out. | |
| // | |
| // Note that I'm assuming Data as the returned value type here as that's the only type I've seen in this | |
| // registry entry. In real code you should check it. | |
| func getProductDescriptionARM() -> String? { | |
| let appleSiliconProduct = IORegistryEntryFromPath(kIOMainPortDefault, "IOService:/AppleARMPE/product") | |
| let cfKeyValue = IORegistryEntryCreateCFProperty(appleSiliconProduct, | |
| "product-description" as CFString, | |
| kCFAllocatorDefault, | |
| 0) | |
| IOObjectRelease(appleSiliconProduct) | |
| if let data = cfKeyValue?.takeRetainedValue() as? Data { | |
| return String(data: data, encoding: .utf8)?.trimmingCharacters(in: .newlines) | |
| } | |
| return nil | |
| } | |
| print("This Mac's UUID from PExpert is: \(getIOPlatformString("IOPlatformUUID", domain: platformExpert) ?? "Not found.")") | |
| print("This Mac's model from PExpert is: \(getIOPlatformString("model", domain: platformExpert) ?? "Not found.")") | |
| print("This Mac's clamshell state from PMRoot is: \(getIOPlatformString("AppleClamshellState", domain: pmRootDomain) ?? "Not found.")") | |
| print("This Mac's product description from AppleARMPE is: \(getProductDescriptionARM() ?? "Not found.")") |
Fixed some ugly code for making Strings.
The code has memory leaks. Need to use takeRetainedValue
The code has memory leaks. Need to use takeRetainedValue
I wasn't super worried about it as it's a playground, but you are correct. I've updated it so that it doesn't catch anyone by surprise.
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Sample output: